Local's Hit

Project of Lecture DBE14 Distributed Systems

Team Members

• Markus Drespling
• Frederick Dehner
• David Lüttmann

Install & run

Install:

1. Update pip: pip install --upgrade pip
2. Update setuptools: pip install --upgrade setuptools
3. Install localshit: pip install -e .

Run frontend server:

frontend

Run backend server(s) with custom frontend server IP:

localshit -f "172.17.0.2"

Open client:

http://[frontend-ip]:8081/index.html

Run tests:

pytest tests -s

Demo Video

Config

All configuration parameters are stored in utils/config.py:

config = {
    "frontend_server": "192.168.0.179",
    "ring_multicast_address": "224.1.1.1",
    "ring_multicast_port": 5007,
    "ring_unicast_port": 10001,
    "content_websocket_port": 10013,
    "frontend_unicast_port": 10012,
    "frontend_webserver_port": 8081,
    "reliable_socket": 10033,
    "loglevel": "debug",
    "chuck_norris": True,
    "quote_intervall": 25,
    "announcement_timeout": 1,
    "heartbeat_intervall": 2,
    "heartbeat_timeout": 6,
}

Docker

You can use docker to run multiple servers on one host. If you use multiple servers distributed on more than one host, use Vagrant because Docker doesn't support bridged networks to the local area network.

Build and run backend

Build Docker image for backends (after every change)

docker build -f Dockerfile.backend -t localshit .

Run docker

docker run --rm localshit

Build and run client

Build Docker image for backends (after every change)

docker build -f Dockerfile.client -t localshit-client .

Run docker

docker run --rm localshit-client

Build and run client

Build Docker image for backends (after every change)

docker build -f Dockerfile.frontend -t localshit-frontend .

Run docker

docker run --rm localshit-frontend

Run tests

pytest tests -s

Details about the system

Message Types

Type	Parameter 1	Parameter 2	Description
SA	IP address	-	Service announcement - announce backend service to multicast
SE	leader candidate IP	isLeader (True/False)	Start election - election messages in the ring
HB	heartbeat GUID	-	Heartbeat messages
FF	IP address of failed node	-	Failure message when heartbeat fails
RP	IP address	-	Reply to sender of service announcement with own IP address
LE	IP address of current leader	-	notifies frontend server about current leader
CO	content	-	Content messages - send to clients
CL	message	-	Notify clients that websocket of backend server is shutting down
CR	comment	-	Message type for comments on quotes from the client
AA	IP address	-	Send initial message via multicast to get a database update

Vagrant

Because Docker doesn't support bridged networking, we choose Vagrant containers with VirtualBox.

Setup

1. Install VirtualBox
2. Install Vagrant
3. Add hashicorp/bionic64 box image: vagrant box add hashicorp/bionic64
4. (Init Vagrantfile: vagrant init hashicorp/bionic64)
5. vagrant up
6. sudo apt-get updates
7. sudo apt-get -y install python3-pip
8. Update setuptools: pip3 install setuptools
9. Install localshit: pip3 install -e .
10. sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.6 1
11. Update pip: pip install --upgrade pip
12. Update setuptools: pip install --upgrade setuptools
13. Install localshit: pip install -e .

Run Vagrant

1. Start vagrant VM: vagrant up
2. Connect to VM via ssh: vagrant ssh
3. Navigate to /home/vagrant/code and start the server with localshit -f "[frontend_ip]"
4. To stop the VM, use vagrant halt

Examples

To run the examles within a docker container use

docker run -it --rm  -v "$PWD/examples":"/usr/src/widget_app" python:3 python /usr/src/widget_app/dynamicdiscover.py